I always had a massive fondness of adventure games in all my gaming life, especially the story driven, slow paced, good old Adventure games of the '90s.
I feel very few games nowadays manage to be immersive, to suck you in their story like adventure games did in their glorious years.
I'm talking about true masterpieces like the first "Longest Journey", with its marvellous story, settings and characters, or "Monkey Island 2", the unreachable peak of comedy in gaming.
But the game that really stole my heart is "Grim Fandango", the last proper adventure game in the history of the genre.
It had everything: beautiful and epic story, fantastic hard-boiled atmosphere (never to be seen again in any game), great characters, wonderful plot....in my opinion simply the Best Adventure Game ever made :)
What about you? Which one do you think is the Best Adventure Game of all times? :)

Sam and Max Hit the Road.

The Longest Journey and, don't stone me for this, it's successor, Dreamfall. I loved both (exclude fighting parts of Dreamfall...), their story, their characters, their... Everything. I hope they'll really make a final part

i'd say The longest journey and Discworld , and right after them come Beneath a steel sky and Broken Sword.
The longest journey is just awesome, it's one of the most beautiful stories i've ever seen, not because it's deep or special, but because of the way it's told and displayed; it just feels real.
Discworld on the other hand is surreal but fun as hell, the universe could be invented by monty python, the humour is just great; only "flaw" is thatthe puzzles are a bit though.
I've never played Grim fandango, i hope GOG puts it up sooner or later.

I'd go for either Day of the Tentacle, or perhaps Space Quest 4 (which is *just* ahead of several other Sierra "Quest" games)

Sanitarium - Only video game that made me cry
Monkey Island 3
Grim Fandango

my top three would be (in no particular order)
Indiana Jones and the Fate of Atlantis
Monkey Island (the original!!!!)
Grim Fandango
Never played Blade Runner or Day of hte Tentacle. I have a soft spot in my heart for all Sierra adventure games, especially Space Quests, but those three are my top rated ones.

I couldn't possibly pick one favourite. I have played and loved so many.
To name a few...
Indiana Jones and the Fate of Atlantis
Discworld
Full Throttle
Sam & Max Hit the Road
Monkey Island I & II
Day of the Tentacle

My top games list is filled with graphic adventures =), so I'll just remove Shadow of the Colossus and the rest from the mix.
1- Riven
2- Myst
3- Gabriel Knight: Sins of the Fathers
4- The Beast Within: A Gabriel Knight Mistery
5- Blade Runner
6- Photopia (not a graphic adventure, but Interactive Fiction; and more like an interactive short story). Available for free from Adam Cadre's page.
LucasArts games are simply a little lower on the list. Don't worry =)

torin's passage lawly adventure game.

No particular order:
Monkey Island 1
Day Of The Tentacle
Zak McKracken And The Alien Mindbenders
Maniac Mansion
Oh, and an honorable mention to Planetfall.
[EDIT] Damn, yes, and Sanitarium. That was a truly stunning adventure game.

Monkey Island 1, 2 and 3
Sanitarium
Gabriel Knight 1, 2 and 3
Day of the Tentacle
Longest Journey
Grim Fandango
Journeyman Project 1 and 2
Discworld
The Moment of Silence
Beneath a Steel Sky
Kyrandia Series
Loom
Daemonica
I have no mouth and must scream
...Yes I know.. alot :)

The Longest Journey and Dreamfall for me.

Grim Fandango, hands down. I LOVED IT.